Aluminum-lithium welding alloys

Abstract

Welding alloys based upon aluminum, copper, mangesium, silver and lithium have been found to possess exceptional properties such as resistance to hot cracking, high strength and ductility, and an unexpected natural aging response. The aluminum-base alloys may contain 3.5 to 7 weight percent Cu, 0.05 to 1.5 weight percent Mg, 0.01 to 2 weight percent Ag, 0.1 to 4 weight percent Li, and 0.01 to 2 weight percent grain refiner.

WHAT IS CLAIMED 
     
       1. A welding alloy for welding aluminum-base alloys, the welding alloy consisting essentially of from about 3.5 to about 7 weight percent Cu, from about 0.05 to about 1.5 weight percent Mg, from about 0.01 to about 2 weight percent Ag, from about 0.1 to about 4 weight percent Li, from about 0.01 to about 2 weight percent grain refiner selected from the group consisting of Zr, Cr, Mn, Ti, B, V, Hf, TiB 2  and combinations thereof, and the balance aluminum and incidental impurities. 
     
     
       2. A welding alloy according to claim 1, wherein the grain refiner is selected from Zr, Ti, or a combination thereof. 
     
     
       3. A welding alloy according to claim 1, wherein the Cu comprises from about 4 to about 6.5 weight percent. 
     
     
       4. A welding alloy according to claim 1, wherein the Mg comprises from about 0.05 to about 1 weight percent. 
     
     
       5. A welding alloy according to claim 1, wherein the Ag comprises from about 0.05 to about 1.2 weight percent. 
     
     
       6. A welding alloy according to claim 1, wherein the Li comprises from about 0.5 to about 2.6 weight percent. 
     
     
       7. A welding alloy according to claim 1, wherein the grain refiner comprises from about 0.05 to about 1 weight percent. 
     
     
       8. A welding alloy for welding aluminum-base alloys, the welding alloy consisting essentially of from about 4 to about 6.5 weight percent Cu, from about 0.05 to about 1 weight percent Mg, from about 0.05 to about 1.2 weight percent Ag, from about 0.5 to about 2.6 weight percent Li, from about 0.05 to about 1 weight percent grain refiner selected from the group consisting of Zr, Cr, Mn, Ti, B, V, Hf, TiB 2  and combinations thereof, and the balance aluminum and incidental impurities. 
     
     
       9. A welding alloy according to claim 8, wherein the grain refiner is selected from Zr, Ti, or a combination thereof. 
     
     
       10. A welding alloy according to claim 8, wherein the Cu comprises from about 4.5 to about 5.5 weight percent. 
     
     
       11. A welding alloy according to claim 8, wherein the Mg comprises from about 0.1 to about 0.8 weight percent. 
     
     
       12. A welding alloy according to claim 8, wherein the Ag comprises from about 0.1 to about 1 weight percent. 
     
     
       13. A welding alloy according to claim 8, wherein the Li comprises from about 0.8 to about 1.8 weight percent. 
     
     
       14. A welding alloy according to claim 8, wherein the grain refiner comprises from about 0.05 to about 0.5 weight percent. 
     
     
       15. A welding alloy for welding aluminum-base alloys, the welding alloy consisting essentially of from about 4.5 to about 5.5 weight percent Cu, from about 0.1 to about 0.8 weight percent Mg, from about 0.1 to about 1 weight percent Ag, from about 0.8 to about 1.8 weight percent Li, from about 0.05 to about 0.5 weight percent grain refiner selected from the group consisting of Zr, Cr, Mn, Ti, B, V, Hf, TiB 2  and combinations thereof, and the balance aluminum and incidental impurities. 
     
     
       16. A welding alloy according to claim 15, wherein the grain refiner is selected from Zr, Ti, or a combination thereof. 
     
     
       17. A welding alloy according to claim 15, wherein the Cu comprises from about 4.8 to about 5.2 weight percent. 
     
     
       18. A welding alloy according to claim 15, wherein the Mg comprises from about 0.2 to about 0.5 weight percent. 
     
     
       19. A welding alloy according to claim 15, wherein the Ag comprises from about 0.3 to about 0.5 weight percent. 
     
     
       20. A welding alloy according to claim 15, wherein the Li comprises from about 1.0 to about 1.6 weight percent. 
     
     
       21. A welding alloy according to claim 15, wherein the grain refiner comprises from about 0.08 to about 0.2 weight percent. 
     
     
       22. A welding alloy for welding aluminum-base alloys, the welding alloy consisting essentially of from about 4.8 to about 5.2 weight percent Cu, from about 0.2 to about 0.5 weight percent Mg, from about 0.3 to about 0.5 weight percent Ag, from about 1.0 to about 1.6 weight percent Li, from about 0.08 to about 0.2 weight percent grain refiner selected from the group consisting of Zr, Cr, Mn, Ti, B, V, Hf, TiB 2  and combinations thereof, and the balance aluminum and incidental impurities. 
     
     
       23. A welding alloy according to claim 22, wherein the grain refiner is selected from Zr, Ti, or a combination thereof. 
     
     
       24. A weld wire having a composition consisting essentially of from about 3.5 to about 7 weight percent Cu, from about 0.05 to about 1.5 weight percent Mg, from about 0.01 to about 2 weight percent Ag, from about 0.1 to about 4 weight percent Li, from about 0.01 to about 2 weight percent grain refiner selected from the group consisting of Zr, Cr, Mn, Ti, B, V, Hf, TiB 2  and combinations thereof, and the balance aluminum and incidental impurities. 
     
     
       25. A weld wire according to claim 24, wherein the Cu comprises from about 4 to about 6.5 weight percent, the Mg comprises from about 0.05 to about 1 weight percent, the Ag comprises from about 0.05 to about 1.2 weight percent, the Li comprises from about 0.5 to about to about 1 weight percent. 
     
     
       26. A weld wire according to claim 24, wherein the Cu comprises from about 4.5 to about 5.5 weight percent, the Mg comprises from about 0.1 to about 0.8 weight percent, the Ag comprises from about 0.1 to about 1 weight percent, the Li comprises from about 0.8 to about 1.8 weight percent, and the grain refiner comprises from about 0.05 to about 0.5 weight percent. 
     
     
       27. A weld wire according to claim 24, wherein the Cu comprises from about 4.8 to about 5.2 weight percent, the Mg comprises from about 0.2 to about 0.5 weight percent, the Ag comprises from about 0.3 to about 0.5 weight percent, the Li comprises from about 1.0 to about 1.6 weight percent, and the grain refiner comprises from about 0.08 to about 0.2 weight percent. 
     
     
       28. A weld wire according to claim 24, wherein the grain refiner comprises Zr, Ti, or a combination thereof.